The present invention relates in general to an apparatus for binding a bundle of paper sheets such as paper money, by winding a binder tape or strip around the paper stack, and in particular to a clamping apparatus for holding the paper stack to be bundled in a pressed or compacted state before and during the tape-winding operation.
In some industrial fields, a plurality of paper sheets are bound or bundled by winding a binder tape or band around a stack of paper sheets, such as paper money, for example. In the process of this winding operation, the binder tape or strip is at first fed from a supply roll and the leading or forward end portion of the tape is inserted in the stack of paper sheets. Thereafter, the tape is wound around the paper stack a desired number of turns and finally the trailing end portion of the tape is cut and bonded to the tape portion wound around the paper stack. An important matter in this bundling operation is to positively and securely bind together the paper stack, thereby preventing the possibility of the bound paper stack from afterward being loosened. In order to inhibit some leaves from being accidentally withdrawn from the bundled paper stack, it is required that the winding tape be wound around the paper stack while the latter is held in a considerably compressed state. In general, a loose stack of paper sheets such as paper money is bulged and has a greater apparent thickness than the net thickness. Under such these loose conditions, the binding of the paper stack will not result in a fixedly and securely bundled paper stack. With a view to avoiding such disadvantages, it has been contemplated that a stack of paper sheets to be bound together maybe held in a forcibly compressed or compacted state during the binding operation. Further, it may occur for those skilled in the art that the paper stack is maintained in a distorted state, e.g. arcuately bent state and the restoring tendency of the bound paper stack from such distorted state to the original flat state after the binding operation is utilized for imparting tension to the bundled paper stack. However, there has hithertofore been proposed no satisfactory apparatus, the operations of which well meet the above requirements.